80's Kos

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JA331

Ride it like you stole it.
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The wait is over! More than 40 years ago I saw a Kos on a riser in the bike section of Myer's department store in Melbourne, Australia. I was 14 at the time and already 6 foot tall riding a 20" dragster and thought this just had to be the greatest thing I had ever seen. However no amount of saving was going to get me that bike as I was working for my father for free on Saturdays and during the holidays. He had 5 kids at private school and luxuries like a Kos were a pipe dream. A few years later I got my driver's license and my focus shifted to cars.

Last week I managed to secure a frame, fork and pair of Araya 7X rims. I could have bought the whole bike but most of the other parts didn't work for me. The seller claims the bike was raced by a friend for a couple of years at a nationally ranked track in New York and then tucked away. Cool story and I should ask if he has any photos of the bike on the track.

As soon as it arrives I won’t waste any time in slamming it together. I will keep the original decals and have already sourced a gold stem and a 175mm Takagi crank. I have had a nos Sugino spider and chainring tucked away for a while waiting to go on the right bike. I'll make a decision on the rims when I see them. As much as I like the original kos bars I would find them too low and they would aggravate the arthritis in my neck. Back in the day, I saved enough to buy a Kos bar and fitted it to a Raleigh 10 speed as well as a pair of Dia-compe mtb brake levers. The bars are long gone but I still have the brake levers.

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The wait is over! More than 40 years ago I saw a Kos on a riser in the bike section of Myer's department store in Melbourne, Australia. I was 14 at the time and already 6 foot tall riding a 20" dragster and thought this just had to be the greatest thing I had ever seen. However no amount of saving was going to get me that bike as I was working for my father for free on Saturdays and during the holidays. He had 5 kids at private school and luxuries like a Kos were a pipe dream. A few years later I get my driver's licence and my focus shifted to cars.

Last week I managed to secure a frame, fork and pair of Araya 7X rims. I could have bought the whole bike but most of the other parts didn't work for me. The seller claims the bike was raced by a friend for a couple of years at a nationally ranked track in New York and then tucked away. Cool story and I should ask if he has any photos of the bike on the track.

As usual, once it arrives it won't take me long to get it together. I'm keeping the original decals on it and have already sourced a gold stem and a 175mm Takagi crank. I have had a nos Sugino spider and chainring tucked away for a while waiting to go on the right bike. I'll make a decision on the rims when I see them. As much as I like the original kos bars I would find them too low and they would aggravate the arthritis in my neck. Back in the day, I saved enough to buy a Kos bar and fitted it to a Raleigh 10 speed as well as a pair of Dia-compe mtb brake levers. The bars are long gone but I still have the brake levers.

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Absolutely love the stays. Is it still called "stays" if it's all one beautiful tube? The Rochester shop sticker is cool too, that isn't all that far from here.
 
The frame and fork arrived today and is in great condition as the seller said it was. It is a 1980 frame which I believe is the first year of production for the Kos. I will get stuck into building it this week. There are some parts still on the way to me so I will resort to using what I have to fill in the blanks. I hope to be able to keep all the original decals. The ones on the seat stays are peeling so I may try fixing them with contact adhesive.

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I got a heap of work done on the kos today. Everything went together easily with the exception of the bent Takagi crank that I got from another source. For the time being I decided to use a new Taiwanese crank I had while I search for another Takagi crank.

Prior to getting started I weighed the frame and fork. The frame is 3.0kg and the fork is 1kg which is impressive for such a big frame with oversize tubing and thick wall head tube and bottom bracket.

I used the wheel set from my ‘68 Typhoon with some new Kenda skinwall tires while I am waiting on a new set of hubs to arrive.

After 4 hours of work my hands are aching but that won’t stop me from finishing it tomorrow and taking it for a ride.

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I got to work early this morning so I could finish off the Kos and take it for a ride later in the day. Fitting the remaining parts went smoothly and then I got stuck into tightening the cranks and tensioning the chain. That’s when the morning turned into a nightmare. The thread on the replacement crank had not being cut correctly which caused the lock nut to strip. I pulled it out, dumped it in the bin and grabbed another new Taiwanese one piece crank I had. This one wasn’t much better as it resulted in uneven chain tension. I ran out of time and had to begin work for the day.

Once that was out of the way, I grabbed the Kos and headed off for a blast to the bay and around town. I felt like a teenager again and was only a few miles into the ride before a couple of kids yelled out to pull a wheelie. I gave them a wave said I would give it go but my mediocre attempt failed to impress.

The ride was going well until the chain came off the first time and then another 2 times after that. It moves along well with it 39-16 gearing and the ride over bumps is awesome, almost Cadillac like and probably the combination of the thin wall light chromoly frame, Brooks B67 saddle and 65psi Kenda tyres. I have over a dozen bikes and this would have to be the best in terms of comfort for a tall rider as the long 23.5” top tube negates the need for a layback seat post. I’m sure the only other
bikes in my fleet with such a long top tube are my 1953 CWC Pleasure liner and 1998 Luxury liner.

Once I returned, I pulled the crank and grabbed a used one from an Electra cruiser I parted out. It was a little shorter at 170mm but at least it sorted out the problem with the uneven chain tension. I now know why I hate 1 piece cranks so much. I’m on the lookout for another period correct Takagi or 3 piece setup.

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With its 4th one piece crank in 2 days and frame and stem pad removed. I prefer the look of the bike without them.
 
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